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Posted in: Nuts and Volts

A Night at the Opera?

April 17  Jeff Eckert

Over the years, many of us have been tempted (or hounded, in the case of Google Chrome) into trying a browser other than the one we’re used to. In many cases, the old won over the new because: (1) It is too much trouble to reset all your passwords and favorite sites; and (2) All browsers are pretty much the same, anyway.

Somehow, the Opera browser has survived even though it commanded a paltry 1.33 percent of the market as of 2016. Recently, the folks at Oslo-based Opera AS (www.opera.com) introduced the Neon browser, which seems to be worth a try. It isn’t really revolutionary, being built atop the same engine as the old one. However, it is “designed to allow users to focus on the most important part of the Internet: the content. Opera Neon will provide users with fun ways to interact with web content, including the ability to drag and push things around, and even to pop content out from the web.”

Most obvious is the user interface, which spreads icons of your favorite sites over the display window instead of in little lists on the periphery. It comes with a built-in ad blocker, plus the left sidebar includes a video player, image gallery, and download manager. It also features a video pop-out that lets you watch videos while browsing other pages, and a split-screen mode that allows two pages to be viewed simultaneously.

In addition, in a trial run on my machine, site access was noticeably faster than with Firefox or Safari. Neon is still a “concept browser,” so rather than replacing the current one, Opera will just incorporate some of its new features into the flagship browser. Windows and Mac users can give it a try for free by linking to www.opera.com/computer/neon.

Posted on 04/17 at 12:00 pm



Posted in: Nuts and Volts

3D Printable Tractor Beam

April 17  Jeff Eckert

Sure, it would be great to have a USS Enterprise-style tractor beam so you could drag alien spaceships out of the sky or even pull your Jeep out of the mud. Sorry, Grasshopper, but we’re not there yet. However, you actually can build your own single-sided acoustic tractor beam, i.e., a device that is capable of trapping and pulling an (extremely small) object using sound waves. We’re not talking about conventional sonic levitation which involves using sound waves to push things away. These tractor beams — based on decades-old fundamentals of physics used to create optical traps — can actually pull objects toward the source. Well, sort of.

According to the inventor, Asier Marzo (a research assistant at the University of Bristol; www.bris.ac.uk), “When you move the tractor beam, the particle moves, but otherwise the trap is static. It can levitate small plastics; it can also levitate a fly and small biological samples. It’s quite handy.”

He continued, “We can modulate a simple wave using what’s called a metamaterial, which is basically a piece of matter with lots of tubes of different lengths. The sound passes through these tubes, and when it exits the metamaterial, it has the correct phases to create a tractor beam.”

The beam can be built from readily accessible components, such as those available from Arduino (www.arduino.cc) for about $70. There are three designs of the device, each with trapping profiles suitable for different object sizes relative to the wavelength of sound used.

For any practical frequencies, the size of trappable objects is limited to a few millimeters.

Posted on 04/17 at 11:46 am



Posted in: Nuts and Volts

Video Games Turn 50

March 17  Jeff Eckert

It seems odd, but last year marked the 50th anniversary of the video game console. The original unit — known as the “Brown Box” — was invented in 1966 by Rudolf Henry Baer, a German-born engineer who was working at Sanders Associates at the time. The device was the first interactive video game system to use a home TV set as the viewing screen, and a later version went into commercial production as the Magnavox Odyssey system.

In subsequent years, Baer helped develop other consoles and consumer games and, in 2006, was awarded the National Medal of Technology for “his groundbreaking and pioneering creation, development, and commercialization of interactive video games, which spawned related uses, applications, and mega-industries in both the entertainment and education realm.” He passed away in 2014 at the age of 92. 

Posted on 03/17 at 2:24 pm



Posted in: Nuts and Volts

Make Your Raspberries Touchable

March 17  Jeff Eckert

If your Raspberry Pi project could benefit from a touchscreen, Winstar Display Co. (www.winstar.com.tw) has you covered. The company has introduced the model WF50BTIFGDHTX five inch HDMI interface mini computer display, employing a resistive touch panel and offering a WVGA resolution of 800x480 pixels. It comes with a control board with an HDMI interface and a 40-pin connector on board; it is specifically designed to simplify Raspberry Pi connection, assuming you also buy the WWHDMI-00 HDMI connector.

The unit isn’t just for the Pi, though; it can be used with any embedded system that has an HDMI output (cable not included). A capacitive version is under development and will be released “soon.” Authorized distributors don’t seem to stock it yet, and pricing info is unavailable as of this writing. Maybe by the time you read this ...
 

Posted on 03/17 at 10:08 am



Posted in: Nuts and Volts

World’s Smallest Transistor — Sort of

January 17  Jeff Eckert

According to the laws of physics, an operational transistor gate can be no smaller than 5 nm, which is about a fourth the size of today’s commercially available 20 nm gate transistors. This is because below 5 nm, a phenomenon called “tunneling” takes place in which the gate barrier can no longer keep the electrons from zipping straight from the source to the drain terminals, and the transistors can’t be turned off. However, lawbreakers at Berkeley Lab (www.lbl.gov) observed that this is true when we’re talking about silicon, but not necessarily other semiconductor materials. By using molybdenum disulfide (MoS2) as the semiconductor material, they managed to create a gate only 1 nm in length. (One nice thing is that MoS2 is not a particularly exotic or expensive material and, in fact, is sold in auto parts stores as a lubricant.)

Part of the explanation as to why the device works is that “electrons flowing through MoS2 are heavier,” so their flow can be controlled with smaller gate lengths. This is something of a head-scratcher, given that yours truly has always been led to believe that all electrons have exactly the same mass. (In fact, Prof. John Wheeler — no slouch in the physics field — went so far as to claim that all electrons are the same because, in fact, there is only one in the entire universe, and we are just looking at it on different slices of space time. But let’s not go there.)

Another factor is that MoS2 can be produced in thinner sheets (≈ 0.65 nm) which also helps to control the current flow.

As with most early developments, it’s a long way from commercial implementation. As observed by Berkeley scientist, Ali Javey, “We have not yet packed these transistors onto a chip, and we haven’t done this billions of times over. We also have not developed self-aligned fabrication schemes for reducing parasitic resistances in the device. But this work is important to show that we are no longer limited to a 5 nm gate for our transistors.”

Posted on 01/17 at 4:38 pm



Posted in: Nuts and Volts

Hardware Design Competition At Diptrace

October 16 

Diptrace PCB design software is holding a hardware design contest for college students and is offering Ca$h to the winner!

Diptrace PCB Design software is holding a design competition open to all college and universtiy level students. If you need extra cash for college or whatever, check out the details at http://diptrace.com/community/student-awards/ Submissions are accepted October 1, 2016 - December 1, 2016.

Posted on 10/16 at 9:55 am



Posted in: Developing Perspectives

The Art of Electronics: What Constitutes the Atomic Level?

June 16  Bryan Bergeron

A recurrent theme when teaching electronics to others is deciding on what constitutes the atomic level of the art; that is, should you discuss the flow of electrons, the fundamentals of Ohm’s Law and discrete components, ICs and other component-level modules, or complete devices at the system level? I guess it all depends on where you’re coming from.

I have to admit a bias toward low level electron physics, simply because that’s how I was first exposed to electronics — the flow of electrons or positrons across barriers and through various crystalline lattices. However, building up from first principles doesn’t seem to fit with the needs of today’s enthusiasts.

For example, take a typical microcontroller. It would take months of study to fully understand the path of an electron from an input pin, through the hundreds or thousands of gates, to one or more output pins. After all that effort, you’d have no better understanding of how the microcontroller operates. No, in this case, a functional understanding at the device level probably constitutes the atomic level. Sure, there are possible exceptions such as internal pull-up resistors in the I/O but — for the most part — a microcontroller can be considered a black box with signal and power inputs and signal output.

The same can be said for single board computers, from smart phones to handheld games. From a system’s perspective, there’s quite a bit to understand, from both the hardware and software sides. It can take months to fully understand a smartphone platform at a high level, and Ohm’s Law isn’t going to help in the process.

So, are component-level electronics dead? I wouldn’t go that far, but I’d say it has become a niche specialty or interest in the electronics enthusiasts community — akin to those who specialize in tube amplifiers. After all, someone has to work at the component level to design the power supply and other system components in the drones, phones, and other consumer electronics.

Looking at my own work in electronics over the past few decades, I can clearly see the progression from component to system level work. I started out with tube and transistor checkers on my workbench, and spent much of my time adjusting the bias on tubes and trying to figure out whether a blown transistor was an NPN or PNP variety with an ohmmeter.

Later, when I worked on commercial communications gear, I simply swapped out boards to identify the faulty circuit. The board went back to the manufacturer for repair. I didn’t even have to heat up my soldering iron.

Today, I’m more apt to turn on my 3D printer than my hot air reworking station, simply because that’s where the action is. I can spend an afternoon creating a robot platform on my printer or the same amount of time replacing a faulty IC on a circuit board. I feel guilty admitting it, but I now get more satisfaction out of creating something of my own design than in simply reworking a circuit. However, time and money being what they are, it’s simply fiscally irresponsible devoting hours and dollars to repairing something that can be replaced with a few clicks of the mouse, with immediate drop shipping from China.

Today, I’d rather spend my time building and flying a drone, focusing on high level topics such as power supply selection, battery charge duration, and maximizing RF signal strength, instead of focusing on what’s happening in the controller circuit.

Has your interest in electronics evolved over the years, or has it remained steadfast on a particular topic or level? Either way, I’d like to hear your story, and what you’ve concluded from your experience.  NV

Posted on 06/16 at 12:48 pm



Posted in: Developing Perspectives

Wall Light Switches: Relics of the Tungsten Age?

May 16  Bryan Bergeron

Given the increased popularity of multi-function light bulbs, it’s clear that the traditional light-only bulb and the associated 110V circuitry are on their way out. I’m not talking about the compact fluorescent (CFC) or even LED “replacement” bulbs, but smart bulbs that do much more than produce heat and light.

I replaced the Tungsten bulbs in my home with 500K or daylight CFC bulbs almost a decade ago. It was an expensive upgrade; in part because the original Tungsten bulbs were still perfectly functional. About a year ago, I started replacing the CFC bulbs with LED bulbs. Again, I tossed completely functional fluorescent bulbs to move up to a cooler operating/more compact light bulb. An added feature was the ability to dim the LED bulbs — something I couldn’t do with a standard CFC.

More recently, I upgraded several of the CFC light bulbs to multi-color LED bulbs that I can operate from my Apple iOS device. With a simple app, I can change the brightness and hue of the lights, set a timer to wake me with light, and operate the lights when I’m away from home. The technology has been around for years, but I’m just getting to the point where I no longer need to look for the light switch when entering a room. My Wi-Fi enabled light bulbs are always on, awaiting my next command. As such, there isn’t a need for the light switch.

My latest journey in light bulb technology does more than simply replace one light source for another. No, the latest generation of always-on “light bulb” replacements makes use of the house wiring and light fixtures, and happens to produce light almost as an afterthought.

For example, Sengled (available at Home Depot and Amazon) offers an integrated microphone/speaker LED bulb that plugs into a standard socket. With the proper peripherals, the bulb supports voice control of cloud connected devices, as well as the ability to detect glass breaking. The Sengled Pulse base serves as a Bluetooth speaker ($150/pair) that is by no means cheap when compared with a standard battery-powered Bluetooth speaker. I found the Pulse to be the ultimate in a low clutter stereo speaker setup.

Then, there are the Wi-Fi repeater bulbs which replace the clunky plug-in desktop repeaters.

At the top on my wish-list for future light bulb “replacements” is an odor detector bulb for my refrigerator that emails me when produce or milk products go bad. I also want an emergency flashlight with a bulb that automatically dials 911 at the press of a button. There are replacement car headlights and tail lights that provide collision avoidance detection, as well. I can even envision a doctor’s penlight that doubles as an optical test device that can diagnose a variety of eye conditions.

As manufacturers are proving, just about any electronic device imaginable can be made to fit the size and power limitations of a traditional screw-in light bulb. I expect the typical technology leapfrogging, with superior offerings from the likes of Philips, GE, and eventually Apple.

Anyone interested in a slightly used set of first generation smart bulbs?  NV

Posted on 05/16 at 12:32 pm



Posted in: Developing Perspectives

Indestructibles: The Lure of Tube Audio Equipment

March 16  Bryan Bergeron

My Sony integrated amp with copper chassis and huge toroidal transformers was a tour de force in my audio setup before the power mains took an indirect lightning hit. Because the microcontroller was fried, I couldn’t even get the unit to power up.

Without access to spare parts — including a new microcontroller assembly — I was at the mercy of factory certified technicians. And — because the unit was just out of warranty — I was going to be out $100 plus shipping in order to get an estimate on the repair.

Well, that amp is still sitting behind my workbench. Someday, I’ll find an identical amp on eBay, buy it for parts, and cobble together something that works. In the meantime, I decided to rebuild a McIntosh 240: a hot, bulky, but virtually indestructible tube amplifier. I spent a weekend replacing the electrolytic capacitors and swapping out the dozen vacuum tubes, one at a time.

The McIntosh 240 — like many other amps from the ‘60s and ‘70s — is unimpressive on paper. A mere 40 watts per channel, total harmonic distortion a whopping 0.5%, and a stripped down weight of 56 lbs. Plus, no remote.

Output is via massive potted output transformers through old-fashioned terminal strips. For less than the price of the vacuum tubes, I could have bought an NAD 3020D or similar solid-state stereo amplifier with superior specifications, the form factor of a paperback, and the all-important remote.

Although I’ll concede on the specifications front, I’ll counter that I prefer the warm coloration that vacuum tubes provide. Most of all, I know that I can repair the amp — regardless of what happens. The transformers are a bit scarce, but can be found on eBay and other online sources.

Otherwise, everything is ordinary electronics stock — capacitors, resistors, diodes, and vacuum tubes. Schematics and manuals are freely available on the Web, and there are numerous third parties that cater to vacuum tube amp owners.

Do I miss a remote? I can live without one. Am I concerned that vacuum tubes are about as far from “green” as an electric toaster? Not really, because I use the amp maybe 30 to 40 minutes a day.

Besides, I’m saving one more device from the landfills. And lightning strikes? Bring them on!

In this era of disposable unrepairable electronics, I suspect that there’s a growing demand for the simpler but workable electronics of the past.

If you’ve recently turned to vintage repairable electronics, I’d like to hear about it.  NV

Posted on 03/16 at 4:21 pm



Posted in: Developing Perspectives

When All You Have is a Hammer

February 16  Bryan Bergeron

A friend in the marketing business contacted me about a project for a local retail store. He wanted to track customer satisfaction as customers exited the store by placing an Arduino-controlled survey taker. Customers would press one of five buttons as they left, indicating their experience from Very Satisfied to Not Satisfied. My friend envisioned five buttons connected to an Arduino, an LCD display, perhaps a beeper for button press feedback, and a battery pack capable of supporting the device for a week.

Seemed like a simple enough task. Too simple, in fact. After working up a straightforward program and defining the base hardware, we naturally progressed to planning a Wi-Fi interface so the counter could be accessed and reset remotely. That would require a simple web page, and maybe a couple hours of programming. We even evaluated a solar powered charger to obviate the need for a plug-in charger.

With plans in hand, we stood back, looked at the hardware and software involved, and the total cost. Then, we revisited the requirements. After a sanity check, we decided the complex Arduino-enabled survey device was overkill.

Starting over without a preconceived product, we identified a solution of five digital mechanical tally counters (or clickers) sold for coaches. We found suitable counters ranging from $2 to $5 each on Amazon. The counters — each the size of a walnut — easily fit on a plastic face plate with cutouts for each counter. And it worked. No batteries to worry about. No programming. And fully reusable counters once the survey was finished. Sure, there was no web interface and no way to check the tally at home on a smartphone, but there wasn’t a need.

The take-away from my experience was to avoid preconceived solutions to new problems. Sometimes expertise in one area unnecessarily narrows the range of options that should be considered when assessing a problem.

The caveat, of course, is that you shouldn’t pass up a chance to learn and expand your skill set. If your goal is to learn to work with an Arduino or other microcontroller and you have the time and funds, then go for it. Given the challenge above, why not have that Wi-Fi interface? Or, automatic cloud upload?

Go wild with the web interface, with visual and audible alarms, and graphics. Just don’t lose touch with what features and functions are really required. Experimenting is fantastic, but know when and how to apply your skills to practical problem solving.  NV

Posted on 02/16 at 1:22 pm